OpenAI Slashes Prices and Expands Limits for Two of Three GPT-5.6 Models

OpenAI has cut prices for two of its three GPT-5.6 models accessed via API: Terra drops 20% to $2 per million input tokens and $12 per million output tokens; Luna drops 80% to $0.20 per million input tokens and $1.20 per million output tokens. The flagship model Sol's pricing remains unchanged. The price reductions also apply to how usage is counted against paid subscription limits in ChatGPT Work and Codex. In ChatGPT and Codex, Free and Go subscribers can use Terra, while Plus, Pro, Business, and Enterprise users can choose Terra or Luna.